NFC enables short-range, contactless, wireless communication between various devices, for example, mobile telephones, service terminals, or kiosks and NFC-compatible stickers, fobs, cards, or tags. NFC requires at least two devices, a first device having a medium for storing data and a second device having at least a reader for reading data. NFC is a form of Radio Frequency Identification (RFID) with a short operating distance, typically requiring proximity of a few centimeters. For example, a reader in the second device can emit a short-range radio signal that when brought into close proximity to the first device can power a chip within a tag in the first device allowing the reader to read the small amount of data that is stored on that chip.
NFC services can include payment services, advertising services, and ticketing services. For example, an NFC-enabled device can be used to make a payment at a point-of-sale terminal, download a coupon from a display at a retailer, or add funds to a transportation ticket at a metro station. The availability of NFC services is often controlled by the operator of the service interface. For example, a retailer may operate a point-of-sale terminal to offer payment and coupon options for products in the retail outlet, and a transportation provider may operate a kiosk in a transportation terminal to offer ticketing options to users of that city's transportation systems. This type of control by the service interface operator can limit the proliferation of useful NFC services.